I know that Make2d is a janky, temperamental beast. Unfortunately, its ability to generate hidden line vectors is something that I need for my workflow, and I don’t know of any other tools that can do it. I’m very interested in any other solutions if you know of any!
The model I’m using Make2d with was not made by me, was provided as an X_T file that I converted with other software.
I have not been using Rhino for very long.
I’ve been running into some strange behavior, Make2d results not matching what I would expect. Here are some examples.
In this case, Make2d wouldn’t show anything on the other side of the hole (purple line). I was able to explode the object and rebuild the surface (red line), and that got Make2d to behave properly. Maybe not the best solution, but it did work.
And this is the problem I can’t find a solution for - Make2d is treating some of the surfaces as sorta partially transparent. I’ve tried adjusting the Absolute Tolerance from .01" down to 0.0000001" (I realize that may not mean much without knowing the model’s scale), with the lower tolerance naturally providing better results.
Any help or insight would be appreciated. I’m primarily using Rhino for this functionality. I know it’s not exactly what it’s built for, but I can’t find any better options. And with not knowing Rhino that well, it’s been quite a bit feeling like fumbling in the dark.
@Helvetosaur I’m happy to help; I appreciate your reply!
I used layers to show the one that was “fixed” with Rebuild vs the original, and I added some results of Make2d next to each of the, with the focal problem parts colored differently to hopefully help you get your bearings. make2d issues.3dm (4.6 MB)
Well, you have a lot of bad objects in there - your “original” polysurface has 36 bad faces… That’s likely the cause of most of your Make2D misery. It’ll take awhile to fix…
Here is a rebuild attempt - lots of stuff untrimmed, retrimmed and fixed… Couple of chamfer surfaces missing on the inside. After all that, there was one surface in there that is out of tolerance (it’s in red), but it seems it was offset 0.07 to the outside.
@Helvetosaur As you suspected, that did work! You have my sincere appreciation for the time and insight you provided, thank you very much. You really went above and beyond.
As I start my first bit of searching to find what’s needed to fix bad surfaces, it definitely seems like it’s well beyond my current familiarity with Rhino. It’s a bit frustrating that these surfaces are being imported with problems since they were provided to me, but that is not your fault at all obviously. And on top of that it’s really helpful to get a lead on what the cause of my problems might be and a potential (if not time consuming) path to fixing it when/if I run into it, once I learn how to do it better!
Bad surfaces in Rhino are almost always due to bad trims. Often they can be fixed by untrimming them (keeping the trim curves) and then re-triming them. Sometimes you need to fix the trim curves first. But it definitely requires some level of expertise to do.
I have a script I developed that attempts to retrim surfaces automatically, I ran it on your surfaces and it fixed all but four. The rest needed some more extensive interventions, including completely remaking them.
Just fixing the bad surfaces using the original trims is sometimes not enough, as you may find that trying to join them back together afterwards will produce bad stuff again as Rhino tries to force edges that are not within tolerance of each other to align so that they may join. So sometimes it can be a real PITA.
As to why you are getting so many bad objects on import, that is a good question to ask. It’s possible to model stuff very cleanly and accurately in many programs (including Rhino) but sometimes the person on the other end lacks the skills/knowledge to do so. So it’s also possible to produce junk, even with expensive MCAD programs. For objects that are relatively mechanical like the one you showed, I daresay it would be almost as fast to model it from scratch in Rhino than dealing with fixing an overly messy import.
Thank you so much for all of the extra info. Just from your previous message, I was able to find and successfully figure out how to un-trim and re-trim, as well as do some manual finagling with that one neck part you highlighted previously. I’m still clumsy like a newborn deer, but at least I have some tools at my disposal rather than just encountering a dead end. HUGE THANK YOU!
In this case, Make2d wouldn’t show anything on the other side of the hole (purple line). I was able to explode the object and rebuild the surface (red line), and that got Make2d to behave properly. Maybe not the best solution, but it did work.
